我希望能够在轻击时切换状态栏的可见性，就像照片应用程序中所做的那样。
iOS 7之前，这段代码运行良好：
-(void)setStatusBarIsHidden:(BOOL)statusBarIsHidden {
_statusBarIsHidden = statusBarIsHidden;
if (statusBarIsHidden == YES) {
[[UIApplication sharedApplication] setStatusBarHidden:YES withAnimation:UIStatusBarAnimationFade];
}else{
[[UIApplication sharedApplication] setStatusBarHidden:NO withAnimation:UIStatusBarAnimationFade];
}
}
但我无法在iOS 7中使其工作。我找到的所有答案都只提供了永久隐藏栏的建议，而没有切换。
然而，既然Photos可以做到，肯定有办法。
在iOS 7或更高版本中，默认情况下，若要隐藏特定视图控制器的状态栏，请执行以下操作：
modalPresentationStyle不是UIModalPresentationFullScreen，则在呈现控制器之前（例如在-presentViewController:animated:completion或-prepareForSegue:（如果您正在使用storyboard）中手动将modalPresentationCapturesStatusBarAppearance设置为YES）。-prefersStatusBarHidden并返回适当的值。setNeedsStatusBarAppearanceUpdate。如果您想要动画效果，请在动画块中执行第三步：
[UIView animateWithDuration:0.33 animations:^{
[self setNeedsStatusBarAppearanceUpdate];
}];
您还可以通过在所呈现的控制器中从-preferredStatusBarUpdateAnimation返回适当的UIStatusBarAnimation值来设置动画的样式。
[UIApplication sharedApplication] setStatusBarStyle:UIStatusBarStyleDefault animated:YES];毫不费力地完成了所有操作。 - Wingzero首先，在Info.plist中将View controller-based status bar appearance设置为YES
这个Swift示例演示了如何在按下按钮后使用动画切换状态栏。
import UIKit
class ToggleStatusBarViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
}
override func prefersStatusBarHidden() -> Bool {
return !UIApplication.sharedApplication().statusBarHidden
}
override func preferredStatusBarUpdateAnimation() -> UIStatusBarAnimation {
return UIStatusBarAnimation.Slide
}
@IBAction func toggleStatusBar(sender: UIButton) {
UIView.animateWithDuration(0.5,
animations: {
self.setNeedsStatusBarAppearanceUpdate()
})
}
}
- (IBAction)toggleUI:(id)sender {
self.hidesUI = !self.hidesUI;
CGRect barFrame = self.navigationController.navigationBar.frame;
CGFloat alpha = (self.hidesUI) ? 0.0 : 1.0;
[UIView animateWithDuration:0.33 animations:^{
[self setNeedsStatusBarAppearanceUpdate];
self.navigationController.navigationBar.alpha = alpha;
}];
self.navigationController.navigationBar.frame = CGRectZero;
self.navigationController.navigationBar.frame = barFrame;
}
- (BOOL)prefersStatusBarHidden {
return self.hidesUI;
}
- (BOOL)prefersStatusBarHidden {
if (_controlsAreHidden == YES)
return YES;
else
return NO;
}
- (UIStatusBarAnimation)preferredStatusBarUpdateAnimation {
return UIStatusBarAnimationFade;
}
-(void)setControlsAreHidden:(BOOL)controlsAreHidden {
_controlsAreHidden = controlsAreHidden;
if (controlsAreHidden == YES) {
// fade out
//
CGRect barFrame = self.navigationController.navigationBar.frame;
[UIView animateWithDuration:0.3 animations:^ {
[self setNeedsStatusBarAppearanceUpdate];
self.navigationController.navigationBar.alpha = 0;
}];
self.navigationController.navigationBar.frame = CGRectMake(0, 20, barFrame.size.width, 44);
}else{
// fade in
//
CGRect barFrame = self.navigationController.navigationBar.frame;
self.navigationController.navigationBar.frame = CGRectMake(0, 20, barFrame.size.width, 64);
[UIView animateWithDuration:0.3 animations:^ {
[self setNeedsStatusBarAppearanceUpdate];
self.navigationController.navigationBar.alpha = 1;
}];
}
}
实际上，现在没有必要搞乱导航栏框架。您只需使用两个单独的动画块即可实现平滑动画。像这样的东西应该可以很好地工作。
@property (nonatomic, assign) BOOL controlsShouldBeHidden;
...
- (void)setControlsHidden:(BOOL)hidden animated:(BOOL)animated {
if (self.controlsShouldBeHidden == hidden) {
return;
}
self.controlsShouldBeHidden = hidden;
NSTimeInterval duration = animated ? 0.3 : 0.0;
[UIView animateWithDuration:duration animations:^(void) {
[self setNeedsStatusBarAppearanceUpdate];
}];
[UIView animateWithDuration:duration animations:^(void) {
CGFloat alpha = hidden ? 0 : 1;
[self.navigationController.navigationBar setAlpha:alpha];
}];
}
- (BOOL)prefersStatusBarHidden {
return self.controlsShouldBeHidden;
}
为了与iOS 6兼容，只需确保检查[self respondsToSelector:@selector(setNeedsStatusBarAppearanceUpdate)]
这段代码完美运行：
-(void)setControlsAreHidden:(BOOL)controlsAreHidden {
if (_controlsAreHidden == controlsAreHidden)
return;
_controlsAreHidden = controlsAreHidden;
UINavigationBar * navigationBar = self.navigationController.navigationBar;
if (controlsAreHidden == YES) {
// fade out
//
CGRect barFrame = self.navigationController.navigationBar.frame;
[UIView animateWithDuration:0.3 animations:^ {
[self setNeedsStatusBarAppearanceUpdate];
self.navigationController.navigationBar.alpha = 0;
}];
self.navigationController.navigationBar.frame = CGRectZero;
self.navigationController.navigationBar.frame = CGRectMake(0, 20, barFrame.size.width, 44);
} else {
// fade in
//
[UIView animateWithDuration:UINavigationControllerHideShowBarDuration animations:^ {
[self setNeedsStatusBarAppearanceUpdate];
}];
double delayInSeconds = 0.01;
dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
[self.navigationController setNavigationBarHidden:NO animated:NO];
navigationBar.alpha = 0;
[UIView animateWithDuration:UINavigationControllerHideShowBarDuration animations:^ {
navigationBar.alpha = 1;
}];
});
}
}
self.navigationController.navigationBar.frame = CGRectZero;
在以下代码行之前，将其插入到您的“淡入”部分：
self.navigationController.navigationBar.frame = CGRectMake(0, 20, barFrame.size.width, 64);
这是必要的，因为框架相同，设置相同的框架将被忽略，并且无法阻止导航栏滑动。因此，您需要将框架更改为其他内容，然后再将其设置为正确的框架以触发更改。
解决此问题的方法取决于您应用程序的plist中“View controller-based status bar appearance”的设置值。
如果您的plist中“View controller-based status bar appearance”为NO，则此代码应该有效：
[[UIApplication sharedApplication] setStatusBarHidden:YES withAnimation:UIStatusBarAnimationFade];
- (BOOL) prefersStatusBarHidden {
// I've hardcoded to YES here, but you can return a dynamic value to meet your needs for toggling
return YES;
}
切换状态时，若您希望根据上述方法的值来更改状态栏的隐藏/显示，您的视图控制器可以调用setNeedsStatusBarAppearanceUpdate方法。